Return on investment — the profit or gain from an investment as a percentage of its cost, via (gain − cost) ÷ cost.

How is ROI different from ROAS?

ROAS is revenue divided by ad spend; ROI is profit-based and should include the full cost picture — a strong ROAS can still be a negative ROI.

What makes marketing ROI honest?

Margin-based gains, all relevant costs included, incremental (not just attributed) credit, and a window that fits the investment.

Growth Marketing Glossary

ROI

noun

The oldest question in business, as a percentage — what did we get back for what we put in?

Schematic — a dollar in, more back

Term: ROI
Part of speech: Noun (acronym)
Field: Finance / Marketing
Formula: (Gain − Cost) ÷ Cost

Forms & parts of speech

ROI · noun

Return relative to cost.

"The campaign's ROI was 40% — $1.40 back for every dollar spent."

Definition in plain terms

ROI — return on investment — measures what an investment gave back relative to what it cost: (gain − cost) ÷ cost, expressed as a percentage. Spend $10,000, get $14,000 of profit-relevant return, and ROI is 40%. It's the universal yardstick for whether money worked.

The mechanics

The formula is simple; the inputs are where honesty lives. Marketing ROI depends on what counts as "gain" (revenue? margin? lifetime value?) and which costs are loaded in (media only, or people and tools too?). It also differs from ROAS: ROAS is revenue ÷ ad spend, gross and channel-level; ROI is profit-based and should carry the full cost picture. A 4x ROAS can be a negative ROI once margin and overhead enter.

When it matters

ROI matters as the shared language between marketing and finance — budgets live and die on it. It misleads when gains are measured on revenue instead of margin, when long-term effects (brand, retention) are invisible to its window, and when attribution feeds it credit-claiming rather than incremental gains. State the inputs, then trust the number.

Worked example. A team reports a triumphant 4x ROAS to the CFO, who asks for ROI instead. On 40% product margins, $40k of ad spend returning $160k revenue yields $64k margin — $24k gain on $40k spend, a real-but-humbler 60% ROI before staff costs. The channel still works; the conversation just got honest. The CFO funds it again, this time trusting the math.

Failure modes to watch. Measuring gains as revenue instead of margin; cherry-picking which costs count; comparing ROI built on attributed (not incremental) gains; and demanding immediate ROI windows from long-horizon brand investments.

Synonyms & antonyms

Synonyms

ROIreturn on investment

Antonyms

ROAS (revenue-based)sunk cost

Usage trends

Search interest for this term over the last five years:

View interest-over-time on Google Trends →

Common questions

What is ROI?: Return on investment — the profit or gain from an investment as a percentage of its cost, via (gain − cost) ÷ cost.
How is ROI different from ROAS?: ROAS is revenue divided by ad spend; ROI is profit-based and should include the full cost picture — a strong ROAS can still be a negative ROI.
What makes marketing ROI honest?: Margin-based gains, all relevant costs included, incremental (not just attributed) credit, and a window that fits the investment.

Related tools & calculators

toolLTV calculator

Resources & people to follow

bookLean Analytics — Croll & Yoskovitz
referenceInvestopedia
thought leaderAvinash Kaushik — analytics

Curated, non-competitor resources verified per term.

Related training

moduleMarketing analytics

Disciplines

Areas of marketing where roi is a core concern:

Marketing analyticsPerformance marketing

Sources

trendsGoogle Trends — "return on investment"